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The default grid system provided in Bootstrap utilizes 12 columns that render out at widths of 724px, 940px (default without responsive CSS included), and 1170px. Below 767px viewports, the columns become fluid and stack vertically.

<div class="row">
    <div class="span4">...</div>
    <div class="span8">...</div>
</div>

As shown here, a basic layout can be created with two "columns", each spanning a number of the 12 foundational columns we defined as part of our grid system.

Offsetting columns

4 offset 4

3 offset 3

8 offset 4

<div class="row">
    <div class="span4">...</div>
    <div class="span4 offset4">...</div>
</div>

Nesting columns

With the static (non-fluid) grid system in Bootstrap, nesting is easy. To nest your content, just add a new .row and set of .span* columns within an existing .span* column.

Example

p>Nested rows should include a set of columns that add up to the number of columns of it's parent. For example, two nested .span3 columns should be placed within a .span6.

Level 1 of column

Level 2

<div class="row">
     <div class="span6">
        Level 1 column
        <div class="row">
            <div class="span3">Level 2</div>
            <div class="span3">Level 2</div>
        </div>
    </div>
</div>

Fluid columns

Percents, not pixels

The fluid grid system uses percents for column widths instead of fixed pixels. It also has the same responsive variations as our fixed grid system, ensuring proper proportions for key screen resolutions and devices.

Fluid rows

Make any row fluid simply by changing .row to .row-fluid. The columns stay the exact same, making it super straightforward to flip between fixed and fluid layouts.

Markup

<div class="row-fluid">
    <div class="span4">...</div>
    <div class="span8">...</div>
</div>

Fluid nesting

Nesting with fluid grids is a bit different: the number of nested columns doesn't need to match the parent. Instead, your columns are reset at each level because each row takes up 100% of the parent column.

Fluid 12

Fluid 6

<div class="row-fluid">
    <div class="span12">
        Level 1 of column
        <div class="row-fluid">
            <div class="span6">Level 2</div>
            <div class="span6">Level 2</div>
        </div>
    </div>
</div>

Fixed layout

The default and simple 940px-wide, centered layout for just about any website or page provided by a single <div class="container">.

<body>
    <div class="container">
        ...
    </div>
</body>

Fluid layout

<div class="container-fluid"> gives flexible page structure, min- and max-widths, and a left-hand sidebar. It's great for apps and docs.

<div class="container-fluid">
    <div class="row-fluid">
        <div class="span2">
            <!--Sidebar content-->
        </div>
        <div class="span10">
            <!--Body content-->
        </div>
    </div>
</div>

What they do

Media queries allow for custom CSS based on a number of conditions—ratios, widths, display type, etc—but usually focuses around min-width and max-width.

Modify the width of column in our grid
Stack elements instead of float wherever necessary
Resize headings and text to be more appropriate for devices

Use media queries responsibly and only as a start to your mobile audiences. For larger projects, do consider dedicated code bases and not layers of media queries.

Supported devices

Bootstrap supports a handful of media queries in a single file to help make your projects more appropriate on different devices and screen resolutions. Here's what's included:

Label	Layout width	Column width	Gutter width
Smartphones	480px and below	Fluid columns, no fixed widths
Smartphones to tablets	767px and below	Fluid columns, no fixed widths
Portrait tablets	768px and above	42px	20px
Default	980px and up	60px	20px
Large display	1200px and up	70px	30px

Requires meta tag

To ensure devices display responsive pages properly, include the viewport meta tag.

<meta name="viewport" content="width=device-width, initial-scale=1.0">

Using the media queries

Bootstrap doesn't automatically include these media queries, but understanding and adding them is very easy and requires minimal setup. You have a few options for including the responsive features of Bootstrap:

Use the compiled responsive version, bootstrap-responsive.css
Add @import "responsive.less" and recompile Bootstrap
Modify and recompile responsive.less as a separate file

Why not just include it? Truth be told, not everything needs to be responsive. Instead of encouraging developers to remove this feature, we figure it best to enable it.

  /* Landscape phones and down */
  @media (max-width: 480px) { ... }
  /* Landscape phone to portrait tablet */
  @media (max-width: 767px) { ... }
  /* Portrait tablet to landscape and desktop */
  @media (min-width: 768px) and (max-width: 979px) { ... }
  /* Large desktop */
  @media (min-width: 1200px) { ... }

Responsive utility classes

What are they
For faster mobile-friendly development, use these basic utility classes for showing and hiding content by device.

When to use
Use on a limited basis and avoid creating entirely different versions of the same site. Instead, use them to complement each device's presentation.

For example, you might show a `<select>` element for nav on mobile layouts, but not on tablets or desktops.

Support classes

Shown here is a table of the classes we support and their effect on a given media query layout (labeled by device). They can be found in responsive.less.

Class	Phones 480px and below	Tablets 767px and below	Desktops 768px and above
`.visible-phone`	Visible	Hidden	Hidden
`.visible-tablet`	Hidden	Visible	Hidden
`.visible-desktop`	Hidden	Hidden	Visible
`.hidden-phone`	Hidden	Visible	Visible
`.hidden-tablet`	Visible	Hidden	Visible
`.hidden-desktop`	Visible	Visible	Hidden

Default grid system 12 columns with a responsive twist

Offsetting columns

Nesting columns

Example

Fluid grid system 12 responsive, percent-based columns

Fluid columns

Percents, not pixels

Fluid rows

Markup

Fluid nesting

Layouts Basic templates to create webpages

Fixed layout

Fluid layout

Responsive design Media queries for various devices and resolutions

What they do

Supported devices

Requires meta tag

Using the media queries

Responsive utility classes

What are they
For faster mobile-friendly development, use these basic utility classes for showing and hiding content by device.

When to use
Use on a limited basis and avoid creating entirely different versions of the same site. Instead, use them to complement each device's presentation.

For example, you might show a `<select>` element for nav on mobile layouts, but not on tablets or desktops.

Support classes

Shocrtcodes - Scaffolding

Default grid system 12 columns with a responsive twist

Offsetting columns

Nesting columns

Example

Fluid grid system 12 responsive, percent-based columns

Fluid columns

Percents, not pixels

Fluid rows

Markup

Fluid nesting

Layouts Basic templates to create webpages

Fixed layout

Fluid layout

Responsive design Media queries for various devices and resolutions

What they do

Supported devices

Requires meta tag

Using the media queries

Responsive utility classes

What are they For faster mobile-friendly development, use these basic utility classes for showing and hiding content by device.

When to use Use on a limited basis and avoid creating entirely different versions of the same site. Instead, use them to complement each device's presentation. For example, you might show a <select> element for nav on mobile layouts, but not on tablets or desktops.

Support classes

What are they
For faster mobile-friendly development, use these basic utility classes for showing and hiding content by device.

When to use
Use on a limited basis and avoid creating entirely different versions of the same site. Instead, use them to complement each device's presentation.

For example, you might show a `<select>` element for nav on mobile layouts, but not on tablets or desktops.